Psoriasis is an autoimmune disease that manifests as plaques on the skin. It occurs when the immune system speeds up the production of new skin cells. The National Psoriasis Foundation notes that while 10 percent of the U.S. population is genetically predisposed to psoriasis, only two percent will go on to develop the condition. In addition to genetic factors, external factors trigger psoriasis attacks. These include stress and injury to the skin. Some drugs can trigger psoriasis.
Propanolol
The beta blocker propranolol, triggers psoriasis in 25 to 30 percent of psoriasis patients taking the drug, notes the National Psoriasis Foundation. Propanolol is a prescription drug for hypertension, heart rhythm disorders and angina. The National Psoriasis Foundation notes other high blood pressure medications may trigger psoriasis, although this has not been confirmed.
Antimalarials
Antimalarial drugs including chloroquine and hydroxychloroquine may exacerbate psoriasis. According to a 1999 research paper published in "Advances in Experimental Medicine and Biology," antimalarials exacerbate latent psoriasis in 18 percent of patients. Lead author Dr. R. Wolf notes that psoriasis clears up completely after withdrawal of antimalarial drugs in 30 percent of patients. Dr. Wolf also notes that antimalarials may also trigger psoriasis in patients who have not experienced the condition previously.
Indomethacin
Indomethacin is a nonsteroidal anti-inflammatory drug (NSAID) indicated to treat pain and inflammation associated with osteoarthritis, rheumatoid arthritis and ankylosing spondylitis. The National Psoriasis Foundation notes that indomethacin may worsen psoriasis, although when indomethacin is taken correctly side effects are limited. Patients who experience psoriasis while taking indomethacin have the option to switch to another NSAID.
Lithium
Lithium is a mood-enhancing drug used to treat depression and manic depression. The National Psoriasis Foundation states that lithium triggers psorisasis in 50 percent of psoriasis patients. Dr. Wolf's research notes that lithium can also induce psoriasis in people that have never experienced it before. Dr. Wolf found that once lithium treatment was withdrawn, 60 percent of patients saw their psoriasis clear completely.
